SOLUTION: Two positive numbers differ by 15 and their product is 324. Find the numbers.

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Question 1083208: Two positive numbers differ by 15 and their product is 324. Find the numbers.
Found 2 solutions by ikleyn, Alan3354:
Answer by ikleyn(52786) About Me  (Show Source):
You can put this solution on YOUR website!
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Let x be the larger number.

Then the other number is x-15.


Since their product is 324, you have this quadratic equation

x*(x-15) = 324,  or

x%5E2+-+15x+-+324 = 0.


Use the quadratic formula to get the solution.

On quadratic formula, see the lessons
    - Introduction into Quadratic Equations
    - PROOF of quadratic formula by completing the square


Also, you have this free of charge online textbook in ALGEBRA-I in this site
    - ALGEBRA-I - YOUR ONLINE TEXTBOOK.

The referred lessons are the part of this textbook under the topic "Quadratic equations".



Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
Two positive numbers differ by 15 and their product is 324. Find the numbers.
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Find a pair of factors of 324 that differ by 15.
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1*324 NG
2*162 NG
3*108 NG
etc
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You can make a quadratic equation, then to factor it, you
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Find a pair of factors of 324 that differ by 15.